From patchwork Tue Jun 15 09:18:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 12320903 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8B0CC49ED9 for ; Tue, 15 Jun 2021 09:18:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFF3361434 for ; Tue, 15 Jun 2021 09:18:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231415AbhFOJU2 (ORCPT ); Tue, 15 Jun 2021 05:20:28 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:54754 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231362AbhFOJUX (ORCPT ); Tue, 15 Jun 2021 05:20:23 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 4DD37219DB; Tue, 15 Jun 2021 09:18:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1623748695; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2y4ATobPVnEcMEJhABd7mhzgYGQRV2///C8khknCrDI=; b=jkrSgf91dMSZKGLpwFnVzcX+RniA5lrBYoOpTKdscfVANjpzuygwReWX45ijFTqHWI/oP5 6SIc40rlo9wSEueoc+eqxwrP39o9wT6pJo8bu1eWvP00C5ncP2WlrT27Hw1Zb0tWoxQpYR LvbV9V92glyJeD13FUgXPPVcUCYib8A= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1623748695; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2y4ATobPVnEcMEJhABd7mhzgYGQRV2///C8khknCrDI=; b=8JAptZxj9cSPv7QkSZ+GkFGANKcsiSwNgVsiI14DugpGsIS+68yIl+moQjnMjZBiYkk9h+ Z1VMWYbCuGHWBYAw== Received: from quack2.suse.cz (unknown [10.100.200.198]) by relay2.suse.de (Postfix) with ESMTP id 36F8FA3BA4; Tue, 15 Jun 2021 09:18:15 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 5BFB01F2CC7; Tue, 15 Jun 2021 11:18:14 +0200 (CEST) From: Jan Kara To: Cc: Christoph Hellwig , Dave Chinner , ceph-devel@vger.kernel.org, Chao Yu , Damien Le Moal , "Darrick J. Wong" , Jaegeuk Kim , Jeff Layton , Johannes Thumshirn , linux-cifs@vger.kernel.org, , linux-f2fs-devel@lists.sourceforge.net, , , Miklos Szeredi , Steve French , Ted Tso , Matthew Wilcox , Jan Kara Subject: [PATCH 14/14] cifs: Fix race between hole punch and page fault Date: Tue, 15 Jun 2021 11:18:04 +0200 Message-Id: <20210615091814.28626-14-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210615090844.6045-1-jack@suse.cz> References: <20210615090844.6045-1-jack@suse.cz> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1533; h=from:subject; bh=ZCABbWCWKurwj2pIQo6pZPjhdXQ595KGSFP8UTIZMfk=; b=owEBbQGS/pANAwAIAZydqgc/ZEDZAcsmYgBgyHBM5bKiu8eYGM3Nz8nWQKIiVrKQrT6ftatfT6be 2XeiCXeJATMEAAEIAB0WIQSrWdEr1p4yirVVKBycnaoHP2RA2QUCYMhwTAAKCRCcnaoHP2RA2di6B/ 45mhRVQnW7UEq8suFiCGDgISonzDUeQNVWEgcLjdXBZEIDbjCB7lYGsbJf/2IQcCDyAp1zJtKbAA97 LKvEdr6VjgcXgV5+oiI4V26Eg4SeicN83dDn0lmsYHvEt32v8FDDtMnb3ANMlKSUEqBQNhPBKvF0Hu 7oan61Xlt9SjuKtR2DNIo6BnoW+d3ctXdP54jBT2o81yaKbIQNLQF1CkZsz+XDP8ihnmg7st97ymKU TPRJSfingbG2ZM2Sp63ozFihnFywZI3GwOjoVYCxmX8taZ69x0x3a1KarULQ8O4uuVOhr+9KDsEgoq Py6BTeucaRFVJYzpQRsDWUnDh/IZou X-Developer-Key: i=jack@suse.cz; a=openpgp; fpr=93C6099A142276A28BBE35D815BC833443038D8C Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Cifs has a following race between hole punching and page fault: CPU1 CPU2 smb3_fallocate() smb3_punch_hole() truncate_pagecache_range() filemap_fault() - loads old data into the page cache SMB2_ioctl(..., FSCTL_SET_ZERO_DATA, ...) And now we have stale data in the page cache. Fix the problem by locking out faults (as well as reads) using mapping->invalidate_lock while hole punch is running. CC: Steve French CC: linux-cifs@vger.kernel.org Signed-off-by: Jan Kara --- fs/cifs/smb2ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 21ef51d338e0..07c9ec047020 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3581,6 +3581,7 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, return rc; } + filemap_invalidate_lock(inode->i_mapping); /* * We implement the punch hole through ioctl, so we need remove the page * caches first, otherwise the data may be inconsistent with the server. @@ -3598,6 +3599,7 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, sizeof(struct file_zero_data_information), CIFSMaxBufSize, NULL, NULL); free_xid(xid); + filemap_invalidate_unlock(inode->i_mapping); return rc; }